I have this list of things I need to know for my Biology test, and there are two questions that I am not sure about. I just want to make sure that I understood the question correctly and that I got the right answer.

Dehydration (condensation) Reaction – two molecules are covalently bonded to each other through a loss of water molecule.
• When a bond forms between two monomers, each monomer gives part of the water molecule that is lost. One provides hydroxyl group (-OH), and another provides hydrogen (-H)
• In order to polymerize monosaccharides, disaccharides, and polysaccharides, such reaction ^ is repeated as monomers are added to the chain by one.
• The cell must have a lot of energy in order to make so many dehydration reactions, and enzymes help the cells to it.

2. Understand hydrolysis of hydrocarbons to monosaccharids

My Answer:

Hydrolysis: reverse of dehydration reaction; to break with water.
Bonds between monomers are broken by the addition of water molecules.
Since monosaccharides are single sugars, they are the building blocks of larger carbohydrates. While carbohydrates form by dehydration reaction, they can also be broken back to monosaccharides by a hydrolysis reaction.

I didn't say you got it right. I can't say that because i don't know exactly what you should have said. I have never heard the term dehidration used for synthesis of complex ploisaccharids. But it seems to be correct. take not also that not all cells have these capabilities

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

Um, for your first post..let me add a few..hope you like it.. condentation reaction is the reaction to dehydrate monosaccharide to form di-, oligo- or poly- saccharide by 'cut' down H atom from one monosaccharide and OH molecule fron other saccharide to form H2O. the remaining sites that had been 'cut' down is only O atoms, so this O atoms form a bond to each carbon group..

H-C-OH + H-C-OH ----> H-C-/OH + H-C-O/H --->[H-C]-O-[C-H] + H2O

I think that's the reaction... hope this clear enough..and sorry if you get more confused by this..

Q: Why are chemists great for solving problems?
A: They have all the solutions.

Yeah, your answers look good though I don't completely understand the second question since its a fairly complex pathway to go from just a hydrocarbon (acetyl in the case of most organisms) to a monosaccharide...

-Jelanen

'It is futile to pretend to the public that we understand how an amoeba evolved into a man, when we cannot tell our students how a human egg produces a skin cell or a brain cell!'